Is there something simmilar to ActionScript: OnFrame(x) do Commands, so there can be script execution at specific frame of Shot ?

In Shot's Command Target rollout, you can add Shot Timer action to do something on certain frame.
Or, you can write codes in the FrameMove() function of User Script File, use GetFrameTime() to test a certain frame.

Thats nice... but is it possible to "jump" to frame something like

if(condition) then go to frame x

, so I can jump to the different parts of scene?

use SetFrameTime()